Three ethylene thiourea-Gehrig's reagent/THF electrolytes were prepared by reacting ethylene thiourea with different Gehrig's reagents EtMgBr/THF, PhMgBr/THF, and PhMgCl/THF. The magnesium deposition-dissolution performance at Pt electrode was tested by cyclic voltammetry. The results showed that the formed ethylenethiourea-Gehr's reagent/THF electrolytes did not change the Mg deposition-dissolution performance of the electrolytes, but broadened their electrochemical windows. For example, the oxidation decomposition potential of the ethylene thiourea-PhMgBr/THF solution could reach 2.3 V (vs. Mg/Mg2+), and the conductivity of the electrolyte increased and then decreased with the increase of the solution solubility, and the highest conductivity of 615 μS-cm-1 was achieved at 0.9 mol-L-1. The electrochemical performance of the Ni electrode showed the highest oxidation decomposition potential of 2.4 V (vs. Mg/Mg2+) and good Mg deposition-dissolution performance. The cycling test of the CR2016 button cell showed that the Mg deposition-dissolution potential on the Ni substrate was lower and its cycling efficiency could reach 92%, which is suitable as a collector for practical batteries.